Rapid advances are being made in the lighting industry for improving the lighting efficiency of luminaires. At least two suggested improvements are useable with substantially collimated light. One of these improvements involves a luminaire which radially polarizes the substantially collimated light. The radially polarized light is used to diminish the veiling reflections from a task surface. Another of these improvements involves a lighting panel for controlling the distribution of light passing through the panel. The light passing through the panel is controlled by using a plurality of light modifying elements for critically reflecting and then refracting such light.
It is common practice within the industry to provide substantially collimated light by disposing a lamp within a parabolic reflector. The reflector is sufficiently large so as to make the lamp appear as a "point source". The light rays that are reflected from the reflector are substantially collimated. However, the direct light rays from the lamp through the luminaire's aperture are not substantially collimated. Some solutions that have been attempted to compensate for these direct rays are the use of caps to mask out these rays and reflectors within the luminaire to return these rays past the light source to the parabolic reflector. These solutions, however, adversely effect the lighting efficiency of such luminaires.
The improved luminaire having an aperture of this invention uses substantially all the light emitted from a light source. A reflector is disposed about a light source and reflects a first portion of light emitted from the light source through a first zone of the aperture to provide a first zonal illumination area. A deviator means is disposed within the reflector for directing a second portion of light different than the first portion of light, emitted from the light source through a second zonal illumination area. Thus, locally unidirectional light is provided across the luminaire aperture since the deviator prevents the direct passage of light rays from the light source through illumination points in the first illumination zone which receive reflected light from the surface of a reflector which is shaped and constructed according to the principles of the present invention.
Further, the improved luminaire may include a light modifying means disposed at least across the first zone of the aperture for controlling light passing through the first zone. This light modifying means is designed to control the distribution of light within a control range. The control is accomplished by using a plurality of light modifying elements with each element designed for critically reflecting the passing light and then refracting such light.